Subsequent Event (Details) (Subsequent Event [Member], USD $)	3 Months Ended
	Jun. 30, 2014	May 05, 2014	Apr. 07, 2014
Subsequent Event [Line Items]
Early Repayment of Senior Debt	$ 200,000,000
Approved dividend, amount per share	$ 0.35
Estimated aggregate dividend payment	396,000,000
Senior Notes [Member]
Subsequent Event [Line Items]
Debt Instrument, Interest Rate, Stated Percentage		5.875%	3.60%
Debt Instrument, Face Amount			$ 1,000,000,000
Debt Instrument, Maturity Date	Dec. 31, 2024
Senior Notes [Member] | Redemption Of Debt [Member]
Subsequent Event [Line Items]
Debt Instrument, Maturity Date	Nov. 21, 2033